Indexes are used in a database to track which documents of a database include a particular value. Indexes however can become problematic when they need to be resized, as the resizing process requires that the existing index is locked, a new index is created, the existing index is copied into the new index, and finally the new value added, before the new index is unlocked. This process of resizing an index consumes valuable system resources and can cause processing delays.
In the drawings, like reference numbers generally indicate identical or similar elements. Additionally, generally, the left-most digit(s) of a reference number identifies the drawing in which the reference number first appears.